1. Field of the Invention
The present invention relates to a support structure configured to support a housing, and an image forming apparatus with the support structure.
2. Description of the Related Art
Optical elements are used in various technical fields. Image forming apparatuses (for example, copy machines, printers, fax machines and combined machines with the functions of the abovementioned devices) utilize optical elements configured to form an electrostatic latent image on a photoreceptor drum. An optical system used in the image forming apparatus is typically stored in a housing of an exposure device.
The image forming apparatus comprises a number of dynamic mechanical elements. For example, the photoreceptor drum mentioned above, a developing device configured to supply toner to the photoreceptor drum, and a conveyor configured to convey a sheet are used as the dynamic mechanical elements. The motions of these mechanical elements potentially cause vibration, which is transmitted to a housing or the other mechanical elements of the image forming apparatus.
Optical facilities utilizing optical elements such as the aforementioned exposure device are more sensitive to the vibration. For example, vibration transmitted to the exposure device through the housing of the image forming apparatus, which supports the exposure device, causes, for example, a jitter image (an image with unintentional streaks).
Support structures configured to proof transmission of such vibration to the optical facilities have been developed. A well-known support structure has, for example, a plate configured to support an optical reader and a vibration-proof spring configured to support the plate, as shown in Japanese Unexamined Utility Model Publication No. 1-93697.
The aforementioned plate is positioned with respect to a chassis by a positioning boss attached to the chassis and a vibration-proof rubber inserted through an opening defined in the plate. It is preferred that a harder vibration-proof rubber be used for the purpose of more accurate positioning. However, the harder vibration-proof rubber usually has worse vibration-proof performance, whereas use of a lower hardness of the vibration-proof rubber for the purpose of better vibration-proof performance results in less accurate positioning of the plate with respect to the chassis.